Vacuum tube assembly apparatus



A. D. GIACCHETTI VACUUM TUBE ASSEMBLY APPARATUS Aug. 21, 1951 5 Sheets-Sheet 1 Filed April '7, 1950 Aug. 21, 1951 A. D. GIACCHETTI VACUUM TUBE ASSEMBLY APPARATUS Filed April '7, 1950 5 Sheets-Sheet 2 Q0 fowl 0f (91/ a H K INN Aug. 21, 1951 A. D. GIACCHETTI VACUUM TUBE ASSEMBLY APPARATUS M 4 5 8 7 w H s n 5 Q A. D. GIACCHETTI VACUUM TUBE ASSEMBLY APPARATUS Aug. 21, 1951 5 Sheets-Sheet 4 Filed April 7, 1950 A g- 1951 A. D. GIACCHETTI 2,564,839

VACUUM TUBE ASSEMBLY APPARATUS Filed April '7, 1950 5 Sheets-Sheet 5 Patented Aug. 21, 1951 VACUUM TUBE ASSEMBLY APPARATUS Anaeleto I). Giacchetti, Chicago, 111., assignor to National Video Corporation, Chicago, 111., a corporation of Illinois Application. April 7, 1950, Serial No. 154,67 8

7 Claims.

ihe present invention relates to assembly line apparatus which is particularly adapted for use in connection with certain stages of processing during manufacture of video transmission and receiving tubes.

Cathode ray picture tubes of the type that are commercially produced for consumer use and which vary in dimensional characteristics present certain assembly line problems which the present apparatus has been designed to simplify and reduce in labor and time consuming respects. It concerns itself with the handling and processing of these tubes after the glass tube envelope has been exhausted and sealed with the terminal base wafer exposed. and the terminal wires which lead to the various gun elements in readiness for securement to the base terminal prongs. The processing which is accomplished during the association with the apparatus new to be described is technologically classified (1) Basing, by which is meant securing the insulated base molding onto the tube neck and soldering the terminals to the base prongs, (2) forming, by which is meant heating the cathode to an increase temperature level for inducing an electrolysis in the chemical coating substances to render them in active condition for electronic emission. Associated with this operation is also the contemporaneously performed getter firing, as a consequence of which P any gaseous molecular traces which have escaped the evacuating process are absorbed, (3) ageing, by which is meant the performance of a continuation of the first-described conditioning of the cathode element under a more moderate heating voltage which accomplishes a more substantial resolution of the emitting surface metallic deposit, and finally, (4) a test ing operation under which standard scanning signals are impressed upon externally disposed magnetic field coils which resemble the coils of conventional receiver apparatus and which impress a test pattern upon the tube screen that is projected on a screen to determine the accuracy of the assembly operations.

The assembly line apparatus which constitutes an illustrative embodiment of the Various features of this invention takes the form of a linear conveyor system mounted on a straight flight supporting table. The tubes are manually placed on individual carrier trucks which are mounted on conveyor rollers directed and aligned in track confinements. The trucks at one point are engaged by flights of endless conveyor chains which are operated in accordance with a control timing arrangement that sets the pace and regulates the progress of the operations. The trucks are provided with apertured seating liners or nest rings and are adapted to receive supplementary liner rings whereby they are made adaptable to various types of tubes, dimensionally speaking. A given number of trucks are installed throughout the conveyor system for carrying the subject products as they are being treated. Thereafter, they are returned at a lower level of the conveyor apparatus to the starting position where they may be re-enlisted into the processing steps successively and continuously at the same pace which prevails in the accomplishment of the various operations.

With each truck, there is associated an upstanding trolley support which carries a distribution of contact wipers. Adjacent the trackway a backboard apparatus is provided on whose surface there are mounted divers bus bars to be engaged by said wipers. The arrangement and distribution of the bus bars is predetermined in accordance with the various operations, that is to say, the presence or absence of various bus bars in certain locations accords with the types of operations which are to be performed at such locations.

For the purpose of accomplishing the displacement of the conveyor trucks from their upper or utility level positions to their lower or returnto-starting-point positions, the instant embodiment contemplates an unique and significant parallel motion elevator linkage, one on each end of the assembly line structure. At the starting end the elevator functions for raising the empty conveyor trucks from the returning level to the loading position, and at the terminal end the same type of elevator apparatus functions to lower the trucks after the tubes have been lifted off manually to the returning level for their journey back to the starting base.

, For a better understanding of the present invention, reference will now be had to the accompanying drawings and to the following detailed specification wherein like reference characteristics indicate corresponding parts throughout.

In the drawings:

Figs. 1a and lb are side elevational views illustrating a complete assembly line apparatus into which has been embodied the various features of the present invention;

Fig. 2 is a transverse sectional view taken approximately on line 2-2 of Fig. 1b;

Fig. 3 is a detail plan view of one of the conveyor trucks with its load content absent and with a portion of the nesting base broken away;

Fig. 4 is an enlarged sectional detail view through one of the conveyor trucks and is taken approximately on line 4-4 of Fig. 3;

Fig. 5 is a fragmentary side elevational view on a moderately enlarged scale featuring one of the trucks and a portion of the bus bar carrying backboard in the proximity of the final or testing region in the conveyor system;

Fig. 6 is an enlarged transverse sectional view taken approximately on line 66 of Fig. 5;

Fig. '7 is an enlarged plan View of one of the lifts or parallel motion elevators at the completion end of the conveyor at an instant when its charge has been removed;

Fig. 8 is an enlarged side elevational view of the apparatus featured in Fig. 7, showing in dotted and solid line disclosure the alternative positions of the lift apparatus; and

Fig. 9 is a rear view of one of the conveyor trucks observed in a direction opposite to that illustrated in Fig. 5.

The principal structural framework upon which the mechanical components of the conveyor are supported. is comprised of a series of spaced angle iron vertical frames H which are made up of front and rear angle iron leg elements spaced apart by top level cross members 12, Fig. 2, and lower level cross member elements l3. Across the length of the conveyor the top level supporting cross members it. afford beam support to the conveyor channels i4 and :5 which are the rearmost and foremost trackway and guide confinements for the wheeled trucks, more particularly described later, and in correspondence therewith the lower level beams is afford similar support to a resembling placement of angle iron guides and IT.

The angle iron trackways l4i5 of the upper level and l6-'! of the lower level extend longitudinally in a parallel and continuous span from the foremost position at the left side of Fig. 1a, to

the rearmost position at the right end of Fig. 1b. The loading operator actuates a director valve which introduces hydraulic fiuid or compressed air into the operating cylinder l8, Fig. 8, causing it to move relative to the stationary piston I 9 between the solid and dotted outlined positions thereat shown, and as a consequence, the lift platform is made to align with the upper or lower.

level trackway systems carrying a single conveyor truck from one of the levels to the other with its load maintained erect. The horizontal level of the platform is maintained at all times by means of the parallelogrammatic linkage consisting of levers 22, one on each side oi the lift base or platform 2!, which pivot at points 23 and 24, and link levers 25 of the same length which pivot at points 28 and 2'!. A strut 2B riveted or welded thereto affords triangulation rigidit to the vertical link 29 in respect to the lift platform 2|, and it is to be understood that corresponding components are provided on both sides of the elevator platform and are similarly pivoted on the end standards H on both ends of the conveyor length.

At the starting point of the lift of Fig. 1a the empty returning trucks are raised from the lower level to the upper level and an operator thereat loads each truck with a video tube 3! disposed with its picture surface downmost and its gun carrying neck uppermost. As has been said, the condition of the product at this point of manufacture contemplates certain prior completions, with the glass envelope completely sealed and evacuated and the electrical connection wires standing outwardly from their glass seal protrusion nipples in which they are imbedded hernietically.

The trucks are manually propelled along a preliminary length of the assembly table designated generally 32, Fig. 1a, and permitted to cluster in close juxtaposition one with the other while attending assembler operators thread the terminal wires through the contact prongs of Bakelite tube bases which possess a characteristic distribution and circular arrangement of rigid terminal prong projection members that are tubular so as to receive the solder wire terminals innermost for securement by dip soldering. The aioredescribed procedure is one which may be accomplished rapidly and eiiectively by the use of speed-up threading tools for directing the relatively thin and flexible wires into the prong tubing, and the short lengths of each wire may be cut off before soldering, if it is so desired to do, or they may be dip soldered simultaneously and cut off there after.

Dip soldering is accomplished at a station designated 33 whereat each tube is reversed in position momentarily by being placed neck down in a hanger bracket 34 which is then adjusted vertically thereby accomplishing a dip operation by means of a pneumatic or hydraulic control piston 35 which raises and lowers the hanger 34, the weight of which is counterbalanced as at 36- as the socket is immersed to a critical depth in a pool of molten solder contained in a heating receptacle 31.

When this operation has been finished the tube is restored to its original neck-uppermost position whereafter the conveyors which carry them approach the backboard 38, from which point forward the truck trolleys 39 engage with their wipers the various bus bars in correspondence with the different treating potentials which are utilized for the specific purposes, as will now be explained.

Referring again to Fig. 1a, attention is directed to the reference numeral 4| which designates generally the beginning of the continuous backboard and also the starting course for the uppermost conveyor chain 42 which is journaled on a sprocket 43 at this end and at a corresponding sprocket 44 near the terminal end of the backboard 38 in Fig. 1b. The conveyor system is preferably synchronized by means of an adjustable timing device or by being appropriately geared to a synchronous motor 45. Coupling between each truck and the conveyor chain 42 may be effected by inserting a coupling pin 46, Fig. through a guide sleeve 41 integral with each truck base 2!. The lower portion 48 of each coupling pin is of a reduced diameter so as to be received between the adjacent block chain links of the belt 42 for confinement longitudinally within the limits of adjacent link pivots thereof.

Each truck is provided with four supporting roller wheels 49 journaled near the corner extremities on each side of the truck, as best indicated in Fig. 2. Side friction with the upstanding webs of the guide rails l4 and I5 is effectively limited by providing guide rollers 5| after the manner indicated in Fig. 3, and in this way there is safeguarded during the movement of the trucks 2| smooth and easy progression, factors which are of material significance towards the fiafe conduct of the delicate apparatus during these severalstages of treatment when but slight jostling and vibration might otherwise tend to inflict damage by way of rupture or misalignment. Each truck'frame 2| is made of a rectilinear integration of angle iron components affording nesting, within which is received a principal supporting base 52 made of a fibrous compressed substance which is possessed of marginal cushioning characteristics and which is centrally apertured as at '53 with a significant diameter of aperture wherein to receive and peripherally support the outermost or flanged diameter of the envelopes 3|, after the manner best indicated in Fig. 2.

Since the bases 52 may be made removably replaceable within the truck frames 21, it is to be understood that conversion of this system to make it readily adaptable to tubes of different diameter or'profile constitutes merely a matter of substitution. Alternatively, the bases 52 may be rigidly secured in the frame members 2 I, and in such instances substitution for varying conditions may be accomplished by the placement within the apertures 53 of adapter frames or thimbles. In order to be able to accomplish continuous test operations for determining the accuracy ofthe assembly and its adaptability to standard sweep circuit controls, it is advisable that bases 52 or their adapter thimbles when so used be provided with adequate central apertures after the manner of those designated 53, so that the impressed images may be projected downwardly upon the reflecting mirrors, which will be described later.

Each truck frame 2| carries at its innermost side a perpendicularly upstanding trolley 39 which is preferably a rigid member made of or carrying a. back panel of electrical insulation, as at 55, on which are mounted a series of contact wipers 56 designated in two groupings as disclosed in Fig. 9 and each insulated from the others so as to be effective for the individual conduction of characteristic voltages divers in quality and timing to accord with the various functions which are performed during the course of travel throughout the extended zone indicated at 51, Figs 1a. and 1b.

At station 4| there may be located a panel board 58 which mounts various meter devices for verifying the potentialqualities on the various bus bars of the backboard 38. At this station, also, the attending operator is equipped with a portable induction heating coil apparatus 59 which he may move and regulate so as to effect alignment with the getter cartridges that are installed adjacent the gun assembly mechanism in each tube neck. Firing of the getter cartridges is thereby accomplished contemporaneously with the initial introduction of the cathode tubes on the backboard courseway. Accordingly, as the high voltage begins to produce the electrolysis reaction liberating oxygen from the various oxide coatings of thecathodes the action of the getter cartridges becomes immediately effective to perform their absorption functions taking up the freed oxygen as well as any other gas molecules which may have escaped evacuation.

After the getters have been fired thereby producing within the tube envelope a condition of final gleaning of molecular gaseous traces which continues thereafter for an indefinite period of time, the tubes are in readiness to receive further processing treatment and testing by having impressed on their electrical elements diiferent voltages which produce aging and testing signals. The electrical connection between the tube socket and the troileys is accomplished by superimposing over each tube neck'a cylindrical hood member 61 which contains a socket base for receiving the prongs of thetube socket 62, Fig. 2, and which is provided with a cable 63 for ex tending the electrical connection between the several projections to the various Wipers '64 and 5B of the trolley .member 39.

During the initial portion of the travel course, generally designated 51, the filament voltage which during functional operation is maintained at 6.3 volts, is raised to a starting voltage of 12 to 13 voltsand thereafter intermittently diminished as the electrolysis reaction progresses. Near the end travel'of this portion of treatment the filament potential is reduced to about 8 volts and thereat continued for 'an extended period of time from 20 to 30 minutes as the surface oxides are further reduced to acquire a predetermined density or depth of deposit, whereafter the voltages are eventually restored to normal operating level as the tube is subjected to magnetic supervision .for the purpose of testing its conduct under sweep circuit regulation.

For this purpose, each of the hoods 61 is equipped with a set of external magnetic coils simulating the deflection control which produces the cathode ray emission sweep movement during video operation. For this purpose, the additional bus bars which appear at station 65, Fig. 1a, are provided and the multiple panel structure 66 thereafter so that test current observations may be made manifest for inspection as the tubes proceed'to the test field near the final portion of the course 51.

Referring now to Fig. 2, which is a section taken at the approach of the picture test area, it will be observed that 'a plurality of angularly .disposed mirrors 6? may be arranged after the manner there indicated suitable for projecting the tube images sidewardly onto an observation screen 68 which will display an enlargement of the pictorial field image thereby affording a performance verification of each tube after it has passed through all of the treating and aging processes aforedescribed. When the tubes reach the final station "H at the end of the conveyor system, they are lifted off and placed into further accommodations for packaging or other disposition. At this station the elevator apparatus lowers the empty truck carriages 21 to the lower level, whereat their coupling pins 46 are installed permitting them to engage the links of a'conveyor chain 12 meshing with sprockets l3 and 14 which returns them under impetus of a gear reduction mechanism or a synchronous motor to the starting position at the lift end of Fig. 1a.

While the present invention has been explained and described with reference to specifically contemplated embodiments and variations, it will be understood, nevertheless, that numerous alternative practices and apparatus are susceptible of being incorporated without departure from the essential spirit or scope thereof. Accordingly, it is not intended to be limited for an understanding of this invention to the particular language employed in the foregoing description nor to the arbitrary illustrations shown in the annexed drawings, except as to extent indicated in the claims appended hereinafter.

The invention claimed is:

1. In a conveyor apparatus for processing and assembling operations, a principal supporting framework having an upper level trackway and a lower level trackway, a plurality of conveyor vehicles advanced on one of said trackways each including a nest base for supporting a vacuum tube envelope in successive stages of assembly line processing, and means at each end of said conveyor system for transferring said vehicles from one of said trackway levels to the other, comprising a movable track section and parallelogrammatic linkage for maintaining the horizontal level of said track section, in combination with pneumatic actuating mechanism for shifting said linkage from each of said levels to the other whilst maintaining parallelism in the horizontal conduct of said track section.

2. In a progressive assembly line system, a framework affording an upper level horizontal route and a lower level horizontal route on each of which are provided opposed guide rails including horizontal and vertical components, a plurality of trucks having roller wheels horizontally pivoted for travel on said guide rail horizontal components and other wheels vertically pivoted for rolling between said vertical components, in combination with platform sections and parallelogrammatic leverage arrangements at each end of said framework for lifting or lowering trucks whilst maintaining them in horizontal level condition from one of said routes to the other.

3. In a conveyor apparatus for assembly line processing, a supporting framework having an upper level trackway and a lower level trackway, a plurality of trucks for travelling on said trackways each truck being equipped for carrying a video tube envelope while advancing through successive stages of assembly line processing on said conveyor, and means at each end of said conveyor apparatus for transferring said trucks from one of said trackway levels to the other comprising an elevator platform and parallelogrammatic linkage for maintaining the horizontal level of said platform, in combination with pneumatic actuating mechanism for raising or lowering said platform from either of said levels to the other whilst maintaining parallelism in the horizontal conduct of said platform.

4. In a progressive assembly line system, a framework affording a horizontal trackway on which are mounted opposed guide rails on different levels, a plurality of trucks having roller wheels horizontally pivoted for travel on said guide rails and guide wheels vertically pivoted for directing travel between said guide rails, in combination with platform sections and parallelogrammatic leverage arrangements for said platform sections for lifting or lowering said trucks from said guide rails at one level to those at another level.

5. An assembly line conveyor apparatus for conducting cathode ray picture tubes during various stages of assembly, comprising an endless conveyor chain driven at a predetermined rate of progression for engaging tandem carrier vehicles which support cathode ray tube envelopes in neck-up position, trolley apparatus associated with each of said vehicles, a flexibly articulated hood member containing a contact socket for receiving the base terminal connections of a cathode ray tube, and a plurality of wipers each electrically associated with one of said hood sockets in combination with a backboard containing spaced bus bars' each corresponding with one of said wipers for communicating various processing and test current potentials from a source of supply through said bus bars to said cathode ray tubes while said vehicles are advanced by said conveyor chain.

6. An assembly line apparatus includin guide rails, an endless conveyor chain driven at a predetermined rate of progression between said rails, a plurality of tandem carrier vehicles carried on said rails and engageable by said chain for supporting cathode ray tubes in neck-up position, a trolley system including wipers carried by each of said vehicles, a hood member electrically connected with said wipers and containing a prong fit socket for receiving the base prongs of oathode ray tubes, and a backboard containing spaced bus bars each cooperating with one of said wipers for communicating various current potentials from sources of supply through said bus bars to said cathode ray tubes while said vehicles are advanced on said conveyor system.

'7. In an assembly line conveyor for supporting and advancing video tubes in process of manufacture including treating stations in which are performed basing, forming, ageing, and testing operations the combination including an upper level flight of trackway extending in a linear horizontal path past each of said stations, a lower level flight of trackway paralleling said upper flight, a plurality of work supporting carriages havin rollers adapted to travel said trackways, elevators at each end of said trackway flights for transferring said carriages individually from one of said flights to the other, a trolley on each of said carriages carrying a plurality of electric contact wipers and a video tube socket for application upon video tube contact prongs, and a backboard supporting in vertical planar alignment, a plurality of current supplying bus bars of length and continuity to correspond with the particular treating station operations whereby engagement of said wipers therewith introduces the predetermined potentials to those of the video tube elements which relate to the various station processing operations.

ANACLETO D. GIACCHETTI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,247,513 Marshaus July 1, 1941 2,324,559 Cooke July 20, 1943 2,358,567 Eitel Sept. 19, 1944 2,398,340 Wilder Apr. 9, 1946 

